docstr: Number of choices
docstr_tok: ["Number","of","choices"]
code: def __len__(self) -> int:
      """Number of choices"""
      return len(self.choices)
  
imports: import numpy
  import nevergrad.common.typing
  from .None import discretization
  from .None import core
  from .None import container
  from .None import _datalayers
  from .data import Array
label_desc: Use image node_id 2 for calling the BaseChoice obj's underlying member method code with example usage: obj.__len__() and returns: len